A study on changes in keratometry readings and astigmatism induced by pterygium before and after pterygium excision surgery
Author(s): Kshama B Popat, Hetaj K. Sheth, Vimal J. Vyas, Matib M. Rangoonwala, Ronak K. Sheth, Jinkal C. Shah
Background: Pterygium is a wing shaped fibrovascular growth of subconjunctival tissue encroaching upon the cornea from the either side within the interpalpebral fissure area inducing significant astigmatism. Surgical intervention for excision of pterygium leads to reduction in astigmatism which significantly improves vision.
Aim: To study changes in corneal astigmatism before and after pterygium excision surgery.
Material and Methods: The study was carried out on 100 eyes of 95 patients who had primary pterygium and were admitted in Department of Ophthalmology, P. D. U. Govt. Medical College, Rajkot and underwent pterygium surgery during period of October 2012 to April 2013. All patients underwent preoperative assessment for visual acuity, anterior segment examination, posterior segment examination, auto refraction and auto keratometry. After pterygium surgery, patients were assessed for visual acuity, auto refraction and auto keratometry on 1st, 7th and 45th post operative day and the results were analysed.
Results: Mean astigmatism preoperatively was found to be 6.20 ± 3.58 Diopters (D) which subsequently decreased to 1.20 ± 1.27 D on 45th post operative day-showing 5.09 ± 3.32 D of change in astigmatism which was statistically significant(paired t-test, p<0.05).
Conclusion: Pterygium causes significant corneal astigmatism, which hampers vision of the patient. Excision of pterygium leads to statistically significant reduction in astigmatism, which improves vision significantly.